1. Which statistics should be reported before the results of a t-test are reported?
The means, standard deviations and number of cases
2. Suppose you read this statement: The differences between the means are statistically significant
at the 0.05 level (t
1. Example 1 on page 119 mentions how many possible explanations for the 3 point difference?
2. What is the name of the hypothesis that states that the observed difference is due to sampling
errors created by random sampling?
The null hypothesis
1. The most important characteristic of a good sample is that it is free from what?
2. If you put the names of all members of a population on slips of paper, mix them, and draw some,
what type of sampling are you using?
3. If there are
1. What is the name of the group of statistics designed to concisely describe the amount of
variability in a set of scores?
Measures of variability
2. What are the two synonyms for variability?
Spread and dispersion
3. If all participants have
1. If you calculated the mean math test score for freshmen and the mean math test score for seniors
and wanted to compare the two means for statistical significance, would a chi-square test be
No, because the Chi-square test is desig
1. If bias has been eliminated, it is safe to assume that the sample is free of sampling errors. Is this
statement true or false?
2. Are the effects of random sampling errors predictable in the long run?
3. If a researchers drew several random s
1. How do statisticians define the term precision?
Precision for statisticians is defined as the extent to which the same results would be obtained if
another random sample were drawn from the sample population (Pyrzcak, p. 95)
2. What is the basic way to
1. What is the full, formal name of the Person r?
Person product-moment correlation coefficient
2. What does a Pearson r of 0.00 indicate?
It indicates the complete absence of a relationship
3. What does a Person r of -1.00 indicate?
It indicates a perfec
1. What is the name of a table that shows how many participants have each score?
2. What does a frequency polygon show?
It is a figure or a drawing that shows show many participants have each score (Pyrczak, p. 31)
3. What is the mo
1. Is an average a descriptive statistic or an inferential statistic?
2. Is the range of a set of scores a descriptive statistic or an inferential statistic?
3. What is the purpose of correlational statistics?
The main purpose of c
1. ANOVA stands for what three words?
Analysis of variance
2. What is the name of the test that can be conducted with an ANOVA?
3. An ANOVA can be appropriately used to test only the difference between two means. Is this
statement true or false?
1. What is the general term that refers to the extent to which two variables are related across one
group of participants?
2. While scattergrams are seldom presented in research reports, they are useful for obtaining what?
A general overview o
1. A direct relationship was found between scores on a reading test and a vocabulary test. This
indicates that those who scored high on the reading test tended to have what kind of score on the
A. High score
2. What is another name for an
1. How is the mean computed?
In order to compute the mean, sum the scores and divide by the number of scores
2. What are the most commonly used symbols for the mean in academic journals?
M (Upper case, italic) should be used for the mean of the entire pop
1. Which average always has 50% of the cases below it?
2. Which average is defined as the most frequently occurring score?
3. Which average is defined as a middle point in a distribution?
4. If you read that the median equals 42 on